curl --request GET \
  --url https://studio.edgeimpulse.com/v1/api/{projectId}/raw-data/ratio \
  --header 'x-api-key: <api-key>'

{
  "success": true,
  "ratio": {
    "training": 123,
    "validation": 123,
    "testing": 123
  },
  "error": "<string>"
}